1. Field of Invention
The present invention relates to a method and apparatus for transmitting and delivering a confidential message or document by way of a conventional facsimile data transmission system in a manner which prevents the casual observer from reading the contents of the received facsimile without producing visible evidence of tampering.
2. Brief Description of the Prior Art
Over the centuries, written communication has become essential to conducting both business and personal affairs. As the subject matter of these communications became increasingly private in nature, there arose a problem regarding their confidential transmission. Short of folding, sealing or encapsulating the message in a sealed tube for delivery, the integrity of those involved in the transmission and delivery of the message was relied upon for preserving confidentiality. A natural solution to this problem was provided in large part by the envelope. To date, the envelope, in its numerous embodiments, is the method of choice to ensure confidentiality through the delivery process.
With the advent of telegraphy, telegraphic messages, such as telegrams, an additional technique of message transmission was established. However, the need for preserving confidentiality rendered this communication technique less than desirable. In response to this problem, U.S. Pat. No. 2,396,833 to D'Humy discloses a telegraph receiving blank adapted to conceal the body of the recorded message, thereby preventing unauthorized access during handling and delivery.
In the decades following the developing of the above-mentioned telegraph receiving blank, a variety of facsimile machines have been developed which incorporate printers utilizing thermally sensitive paper. Machines of this type are generally adapted to receive and print messages of varying length and thereafter automatically cut the thermally sensitive paper at the end of the message.
As with previous technology involving written communication, present day facsimile machines have not been without concern regarding confidentiality. However, prior art recording blanks of predetermined length have been incapable of safeguarding confidentiality since, unlike prior telegraph equipment, modern day facsimile machines often sever the paper at the end of the recorded message, thereby resulting in documents of varying length. Consequently, the continuous strip of facsimile printing medium proposed in U.S. Pat. No. 3,396,833, cannot be successfully utilized with thermal printing facsimile machines since the severing operation, occurring at arbitrary points along the continuous strip, frequently severs the sealed blank along the message recording area, rendering it impossible to ensure that intended address information is obtained without revealing confidential information. Similarly, the rolls of printing medium disclosed in U.S. Pat. No. 5,001,749 also cannot be successfully utilized with the thermal printing facsimile machines since, with arbitrary length cutting, it is not possible to ascertain intended addressee information without revealing confidential information.
Although attempts at securing confidentiality in facsimile transmissions through the use of specialized recording blanks and material have been virtually unsuccessful to date in thermal facsimile printers, alternative techniques do ensure some measure of confidentiality.
U.S. Pat. No. 4,876,355 discloses one such technique in which a patterning device in conjunction with a photocopy machine is used to produce two partial documents. These partial documents are then transmitted by a facsimile system, and subsequently registered at the receiver to reconstruct the original document. While this technique prevents unauthorized casual reading of each partial document at the transmitter, the received partial documents can be easily registered by unauthorized personnel for document reconstruction without leaving any evidence that unauthorized access had occurred.
Another technique for securing facsimile transmissions has been through the use of facsimile machines having "electronic mailbox" capabilities. In such systems, confidential messages destined for a particular individual are not printed upon receipt, rather they are stored in an assigned electronic mailbox or memory location within the facsimile machine. When the individual desires to read his or her mail, an assigned access or security code is inserted, whereupon the stored messages are printed. While this technique can provide a certain degree of confidentiality, it requires special equipment and necessitates that the recipient or an authorized agent access it from the facsimile machine.
Thus, while several approaches have been proposed for preventing casual reading of confidential messages, such techniques have suffered from shortcomings and drawbacks of the type described above.
As a result, there remains a need for an alternative approach in delivering hard-copy facsimiles containing confidential information in a manner which prevents causal reading of the contents of the confidential document, and overcomes the shortcomings and drawbacks associated with the use of prior art composite recording medium in conventional thermal printing facsimile equipment having arbitrary sheet length cutting capabilities.
Accordingly, it is a primary object of the present invention to provide flexible composite material and a method of delivering hard-copies of confidential messages in a manner which overcomes the shortcomings and drawbacks of prior art methodologies and apparatus.
It is a further object of the present invention to provide such flexible composites for use in conjunction with a conventional facsimile data transmission systems.
It is a further object of the present invention to provide such a method, facsimile instruction labels and composite recording material, in which confidential messages of any length, can be electronically transmitted and subsequently printed as a hard-copy facsimile which permits delivery to the intended addressee without revealing its confidential content.
Still a further object of the present invention is to provide such a method and apparatus, in which confidential documents are formatted so that a non-confidential portion of the facsimile message is simply rendered visible for reading sender delivery instructions, while the confidential message portion is concealed in a manner that would provide visual evidence of tampering.